Dehumidifier for air utilized in laundry drying

ABSTRACT

A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry by machine. The dehumidifier is mounted in a laundry machine of the type having a generally rectangular cabinet, and includes a generally rectangular housing. A plurality of generally horizontal, water filled, shallow trays are mounted within the housing in overlapped, vertically spaced relation. The arrangement of the trays is such as to cause a downward zigzag flow of water from one tray to the next. The hot moisture laden air is guided across the tray so that the air is cooled and dehumidified during the passage.

Sarukahanian et al.

DEHUMIDIFIER FOR AIR UTILIZED IN LAUNDRY DRYING lnventors: Georg Sarukahanian; Manfred Kriiger, both of Berlin, Germany Assignec: Siemens Electrogerate GmbH, Munich, Germany Filed:

Aug. 31, 1972 Appl. No.: 285,135

Foreign Application Priority Data Sept. 17, 1971 Sept. 23, 1971 Sept. 29, 1971 Nov. 2, 1971 Mar. 23, 1972 Mar. 23, 1972 Mar. 23, 1972 US. Cl

Int. Cl.

Germany 2214621 I Field of Search 34/77, 78, 131,75, 231, 34/199, 82; 55/240, 229, 241, 244;

References Cited UNITED STATES PATENTS Feb. 18, 1975 761,042 5/1904 Gathmann 34/77 1,800,724 4/1931 E1110 261/114 R 2,149,362 3/1939 Riegler 261/114 R 2,983,493 5/1961 Handwerk.... 261/109 3,064,358 11/1962 Gluffre 1 34/77 3,218,730 11 1965 Menk et a1 34/77 FOREIGN PATENTS OR APPLICATIONS 1,439,529 6/1965 France 34/75 Primary ExaminerCarroll B. Dority, Jr.

Assistant Examiner-Larry L. Schwartz Attorney, Agent, or Firm-Kenyon & Kenyon Reilly Carr & Chapin [5 7] ABSTRACT A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry by machine. The dehumidifier is mounted in a laundry machine of the type having a generally rectangular cabinet, and includes a generally rectangular housing. A plurality of generally horizontal, water filled, shallow trays are mounted within the housing in overlapped, vertically spaced relation. The arrangement of the trays is such as to cause a downward zigzag flow of water from one tray to the next. The hot moisture laden air is guided across the tray so that the air is cooled and dehumidified during the passage.

15 Claims, 7 Drawing Figures PATENTED 3,886,333

SHEET 2 OF 2 Fig.5

Fig.6

WWW

Fig.7

DRYING BACKGROUND OF THE INVENTION This invention relates to a dehumidifier of the type utilized to remove water from heated, moisture laden air produce during the drying of laundry by machine.

In the drying of laundry by machine it is common to utilize drum type laundry dryers in which hot air is passed through a perforated drum rotating about a horizontal axis to remove moisture from wet laundry placed within the drum. Once the hot air has become saturated with moisture it is necessary to remove it as rapidly as possible from the vicinity of the dryer for efficient drying. If the dryer is installed in a location (e.g., abasement laundry room) where the discharged moisture laden air cannot easily be vented straight to atmosphere, as is sometimes the case, there may be a problem of build up of moisture laden air in the vicinity of the dryer which will eventually reduce drying efficiency and create unpleasant conditions of high local humidity. It is therefore desirable to dehumidify the moist discharged air, one method being to pass it over cold surfaces to condense the water vapor.

For example, it has been known to pass the moisture laden air over walls cooled by water directed against them through fine spray nozzles. However, the use of such a system can present problems as stray lint, commonly found in the discharge air from a laundry dryer, can cause clogging of the spray nozzles. Other problems have also been known to arise with dehumidifiers utilizing water cooling in that such prior devices have generally required to be mounted in very accurate vertical alignment of their internal water flow. As a result difficulties may be encountered when such units are installed on uneven floors or under other out of horizontal conditions.

SUMMARY OF THE INVENTION A dehumidifier constructed in accordance with the present invention is particularly effective in removing water from the hot moisture laden air produced during the drying of wet laundry by machine.

In more detail a dehumidifier according to the invention is intended for installation in a laundry machine,

' which may be either a laundry dryer or a laundry washing machine, having a generally rectangular cabinet. The dehumidifier includes a generally rectangular housing mounted within the cabinet of the laundry machine. A plurality of generally horizontal, water filled, shallow trays are mounted within the housing in overlapped, vertically spaced relation. The trays are arranged to cause a downward zigzag flow of water from one tray to the next. Heated, moisture laden air created during the drying of wet laundry is passed in a meandering path across the water filled trays so that the air is cooled and dehumidified during its passage.

BRIEF DESCRIPTION OF THEDRAWINGS.

A dehumidifier constructed in accordance with one preferred embodiment and certain additional embodiments of the invention, is illustrated in the accompanying drawings in which:

FIG. 1 is a cross-sectional side view of a laundry dryer in which is mounted a dehumidifier constructed in accordance with the preferred embodiment of the invention,

FIG. 2 is across-sectional end view of two water filled trays and an associated overflow system constructed according to a second embodiment of the invention, FIG. 3 is a cross-sectional side view of a dehumidifier constructed in accordance with a third embodiment of the invention, FIG. 4 is a cross-sectional side view of a dehumidifier constructed in accordance with a fourth embodiment of the invention,

FIG. 5 is a simplified side view of the laundry dryer and associated dehumidifier shown in FIG. 1,

FIG. 6 is a cross-sectional side view ofa dehumidifier according to a fifth embodiment of the invention; and FIG. 7 is a top view of one of the trays utilized in the dehumidifier shown in FIG. 6.

DETAILED DESCRIPTION Referring to FIG. 1 of the drawings, a dehumidifier constructed in accordance with the preferred embodiment of the drawings is there shown, installed in a laundry dryer. The dehumidifier could, however, alternatively be installed in a washing machine with ducting to the outlet of an adjacent laundry dryer.

The laundry dryer includes a conventional, generally rectangular vertical cabinet 10 and a perforated drum 11 mounted for rotation about a horizontal axis within the cabinet. Air is blown through an inlet channel I2 provided with a heating element 13 from the outlet of an electrically driven blower I4 and passes through an injection grill 15 into the drum II and the wet laundry within the drum. The forward wall of the cabinet 10 is provided with an inwardly projecting annular wall 16 whose inner edge functions as the front bearing ring for the drum 11. A hinged circular door 17 closes an opening 18 defined by the annular wall, which permits access to the drum interior. Air leaving the drum passes through a peripherally extending annular slot in the underside of the annular wall 16, which communicates with the interior of a downwardly extending duct 20.

A dehumidifying unit 21 constructed in accordance with the preferred embodiment of the invention is mounted in the lower part of the laundry dryer below the drum. The dehumidifier includes a generally rectangular housing22, the front wall of which is constituted by a front wall 10a of the laundry dryer cabinet. Mounted within the interior ofthe housing 22 are a plurality of horizontal shallow trays 23 supported in over lapped vertically spaced relation by conventional bracket (not shown) on which they rest in lift-off relation so that the trays are easily removable for cleaning. To provide access to the interior of the dehumidifier unit for cleaning and periodic removal of lint, a door 26 communicating with the interior of the housing 22 is provided in the front wall 10a ofthe cabinet. Water is supplied to the trays by an inlet conduit 9 spaced above the uppermost of the trays 23 extending in a transverse direction. The inlet conduit is a pipe provided with axially spaced, downwardly directed holes, or with a downwardly directed channel along its lower surface, thus obviating the disadvantages of prior devices utilizing fine spray nozzles which could easily become clogged with lint. Each of the trays 23 is filled with water and there is a flow of water in zigzag relation from the uppermost to the lower-most tray. The trays are disposed at a slight inclination from the horizontal with the lower, downstream end of one tray adjacent the upper, upstream end of the next underlying tray to achieve the desired zigzag flow.

Moist air is delivered to the interior of the housing 22 adjacent its bottom forward corner through a convergent nozzle-like lower region 200 of the previously mentioned duct 20. The moist entering air flows over the trays 23 in a meandering path in counter-current relation to the flow of water there along and exists in the upper rear corner of the housing where it is delivered through an opening 28 to the inlet side of the previously mentioned blower 14 to be recirculated through the dryer. As the hot, moist air passes over the cooling water in the trays, it is cooled and the moisture in the air condenses and falls into the trays and also on to the bottom wall 24 of the housing which is inclined downwardly and forwardly.

Water leaving the bottom one of the trays 23, as well as other droplets and condensed moisture on the sides of the housing, flows along the downwardly inclined lower wall 24 of the housing to a sump 30 configured as a transverse, downwardly extending indentation po-- sitioned at the forward end of the lower wall 24. The sump 30 is positioned directly under the discharge opening at the lower end of the extension a of the duct 20. The convergent shape of the lower portion 20a of the duct increases the velocity of the air being discharged into the dehumidifier housing so that the en tering air is directed rapidly into the water in the sump. It has been found that this arrangement assists in separating out lint carried through in the entering air by improving the mixing that occurs between the incoming air and the cooling water in the sump 30. As a constructional detail, the forward transverse vertical wall of the tapered duct portion 20a can be carried by and fixedly secured to the interior of the previously mentioned removable door 26.

The previously mentioned trays 23 are preferably fabricated of a highly heat conducting material and are in addition, preferably, nonrusting sheet metal. To provide rigidity for them, the sheet material may be reinforced with edge beads or lips which additionally constitute the side walls to contain the water within the tray. Water flows by gravity from the lower, deownnally extending downwardly curved, dished portions 34 extending along the center line of the tray on opposite transverse sides of the center line. The tray is provided with sidewalls 36 extending along each of its longitudinal edges and is closed at its upstream and downstream ends by transversely extending vertical end walls. Adjacent the downstream end of each tray an overflow pipe 38 is positioned on the center line of the tray projecting upwardly into its interior to a level just below the upper edges of the lips 36 and the front and rear end walls. As a result liquid within the tray does not enter the overflow pipe until the liquid is almost at the point of overflowing. The lower end of the overflow pipe 38 extends downwardly and projects below the surface of the water at the upstream end of the underlying tray so that the possibility of vertical flow of the air through the pipe is prevented. A sufficient gap is allowed between the top of the overflow pipe and the upper edges of the side and end'walls to enable the equipment to continue to function even when installed in areas of minor deviation from the horizontal which cannot easily be achieved otherwise.

To provide for complete drainage of the trays when the equipment is not in use, each of the tray portions 34 at its lowest point of curvature and adjacent its lowest downstream end is provided with a small drain opening 40. The collective flow of water through the drain holes 40 is considerably less than the flow of water through the device for the inlet conduit 9 when the device is operating. However, when the dehumidifier is shut down, each of the trays will eventually empty itself through its associated drain holes 40.

Another form of tray construction shown in FIG. 7 includes raised beads 43 extending along and defining the side walls of each tray so that the base of the tray and the area between the beads constitutes the water flow channel. The beads may be extended into the center of the tray at its outlet end to define an outlet spout 44 through which water leaving the tray is directed to the upstream end of the next underlying tray. Each tray may be mounted at a slight downward inclination from its upstream to its downstream ends to enhance the flow of liquid. In addition, transversely extending upward projections 46 may be provided extending partially across the flow of water within the tray so as to provide it with an extended, convoluted path of flow.

In a third embodiment of the invention shown in FIG. 3, utilizing two of the previously mentioned trays 23, the housing is additionally provided with a transverse, internal drip board 62 fixedly secured to the underside of a horizontal upperwall 63 of the previously mentioned housing. The drip board 62 is positioned adjacent the forward end of the uppermost of the trays 23 and extends downwardly and rearwardly. Its effect therefore is to direct the air downwardly and toward the water in the surface of the uppermost of the trays 23 and by constricting the cross-sectional area of the tray to increase its velocity. At the rearward end of the uppermost tray 23 is positioned the inlet pipe 9 for the water and spaced closely above that is a transversely extending lamina supported by conventional bracketing to the remainder of the housing 22. The lamina 60, which projects horizontally into the air stream prevents droplets of the cooling water from being carried through the outlet 28 due to the development of vortices in the air stream. In the occasional event that droplets of water should escape, however, they run off a downwardly inclined rim 61 along the rear edge of the lamina 60 and fall to the bottom wall of the housing 24 and the sump 30.

The drip board and the lamina assist in assuring that no moisture is carried out through the dehumidifier housing and retransmitted to the drum through the blower 14, which would reduce the efficiency of the installation. Thus the dehumidifier operates so that, on the one hand, provision is made for separating out a moisture in the air steam passing through the dehumidifier while assuring on the other hand that no cooling water'droplets are carried along into the air inlet due to the development of vortices in the air flow.

To further insure that droplets of water are not carried through into the inlet of the blower, the drip board 62 may be made an integral part (FIG. 4) of the previously mentioned upper wall 63 of the housing. In additional a second sloped portion 64 of the wall 63 may be provided extending from adjacent the rear end of the drip board 62 to a position spaced above and adjacent the rear end of the upper tray 23. As before the portion 62 insures that the air is directed against the cooling water in the upper tray. In the region of the second portion 64, droplets are carried in an ascending direction and are prevented from entering the entrance 28 to the blower by a transversely extending dependent drip edge 65 secured to the rear end of the wall 64.

The previously mentioned lower portion a of the duct through which the hot moist air is introduced into the housing, includes a vertical rear wall 80. Because the rear wall faces the interior of the housing, which is relatively cool, the wall 80 might become somewhat cooled which could lead to partial condensation of moisture within the duct portion 20a that would promote lint deposition within the duct. To prevent this undesirable effect it is advisable to insulate the rear wall 80 so that it does not become to cooled relative to the remainder of the lower duct portion 20a. For this purpose a second wall 81 spaced from and coextensive with the portion of the wall 80 entering the housing, is provided. The air space 82 between the walls 81 and 80 is sufficient to provent relative cooling of the wall 80. Additional insulation material may be placed within the space 82 if desired.

To screen out lint particles picked up during the pas sage of the drying air through the laundry, a lint filter 19 (FIG. 1) is positioned in overlying relation to the peripheral opening in the annular wall 16, through which the discharged air enters the duct 20. To provide an opening for the passage of lint in the event that all the mesh openings of the lint filter are allowed to become clogged, a transverse slit 70, of about 0.5 to l centimeter width, extends across the entire width of the filter. The edges of the slit are stiffened by flanges 71 secured to the adjacent portions of the dryer. Lint clusters passing through the slit 70 are carried straight down the duct 20 and 20a and are deposited in the water in the sump. The slit shape opening 70 is located in the last third of the lint filter as seen in the direction of rotation of the drum, so that all the regions of the filter preceding the slit can pass the lint accumulated in them to the slit shaped opening.

A further embodiment of the invention in which the flow of water is in the same direction as the flow of air, is illustrated in FIG. 6. in this arrangement, the lower portion 20a of the inlet duct is omitted so that air entering through the duct 20 arrives at the upper end of the housing. Mutually inclined trays 76 of the type shown in FIG. 7 (and previously discussed in relation to that figure) are arranged for zigzag flow of water in a similar manner to that previously described. The uppermost of the trays 76 extends directly beneath the inlet of air from the duct 20 so that flow of air is in the same direction as the flow of water. Water is directed to the upstream edge of the top tray 76 through a transverse channel 78 at the forward upper end of the housing having an opening 80 through which the flow of water is directed onto the upper tray. Control of the flow of moisture laden air produced during the drying of laun-.

dry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising,

a generally rectangular housing mounted within the cabinet,

a plurality of generally horizontal, water filled, shallow trays mounted within said housing in overlapped, vertically spaced relation, said trays extending in a generally longitudinal direction with the flow of water along each said tray being from one longitudinal end to the other, each said tray further including adjacent its downstream end an overflow pipe positioned transversely at approximately the center of said tray, said overflow pipe extending upwardly in such relation to the vertical dimensions of said tray that overflow of water occurs only when said tray is nearly filled with water, each being configured so as to have longitudinally extending, downwardly curved portions positioned on either transverse side of said overflow pipe with a drain opening positioned at the lowest point of curvature, said trays being arranged to cause a downward zigzag flow of water from one said tray to the next, and

means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby.

2. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising,

a plurality of generally horizontal, water filled, shallow trays,

a generally rectangular housing mounted within the cabinet, said trays being mounted within said housing in overlapped, vertically spaced relation and being arranged so as to cause a downward zigzag flow of water from one tray to the next, said housing extending in a rearward direction from the forward wall of the cabinet, and including a first downwardly and rearwardly inclined protion spaced above and adjacent a leading end of the uppermost of said trays, said first portion of said housing directing the flow of air downwardly against said tray, a second inclined portion of said housing extending from a position adjacent the rear edge of said first portion inclined upwardly and extending rearwardly, and a third portion of said housing extending vertically between the adjacent ends of said first and second inclined portions of said housing, and

means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby.

3. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising,

a plurality of generally horizontal, water filled shallow trays,

a generally rectangular housing mounted within the cabinet, said trays being mounted within said housing in overlapped, vertically spaced relation and being arranged so as to cause-a downward zigzag flow of water from one tray to the next, said housing extending in a rearward direction from the forward wall of the cabinet and including a first downwardly and rearwardly inclined portion spaced above and adjacent a leading end of the uppermost of said trays, said first portion of said housing directing the flow of air downwardly against said tray, a second inclined portion of said housing extending from a position adjacent the rear edge of said first portion inclined upwardly and extending rearwardly, and a dependent, transversely extending lip secured to said second inclined portion of said housing adjacent the rear end thereof, and means for guidingthe air across said trays to cause the air to be cooled and dehumidified thereby.

4. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising,

a generally rectangular housing mounted within the cabinet,

a plurality of generally horizontal, water filled, shallow trays mounted within said housing in overlapped, vertically spaced relation, said trays being arranged to cause a downward zigzag flow of water from one said tray tothe next;

means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby;

a vertical duct extending into a forward end of said housing, said duct having an upper end positioned outside said housing supplied with the heated, moisture laden air, and an open, discharge end positioned near the bottom of said housing adjacent a forward end thereof, said trays having their forward ends positioned adjacent and spaced from said duct extending rearwardly therefrom, said duct decreasing progressively in cross-sectional area toward said discharge end thereby increasing the velocity of the air flow entering said housing.

5. A dehumidifier as defined in claim 4 wherein said housing is positioned adjacent the front wall of the cabinet of the machine, and includes a forward wall defined by an adjacent portion of the forward wall of the cabinet, said housing further comprising a service door mounted in said housing forward wall for providing access to the interior of said housing and means for removably mounting said trays therewithin.

6. A dehumidifier as defined in claim 4 wherein each of said trays is formed of sheet material provided with raised beads along its peripheral edges, said trays being arranged at a slight inclination to the horizontal and being provided with raised projections extending substantially transversely to the flow direction of the water within said tray.

7. A dehumidifier as defined in claim 4 further including,

asump in the bottom of said housing for collecting water, said sump positioned vertically beneath said discharge end of said duct. 8. A dehumidifier as defined in claim 4 wherein said housing further includes,

guiding surfaces connected with said housing extending downwardly and toward the upper surface of the uppermost of said trays for guiding the flow of air against the water in said uppermost of said trays. 9. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising,

a generally rectangular housing mounted within the cabinet,

a plurality of generally horizontal, water filled, shallow trays mounted within said housing in overlapped, vertically spaced relation, said trays being arranged to cause a downward zigzag flow of water from one said try to the next, said trays extending in a generally longitudinal direction with the flow of water along each said tray being from one longitudinal end to the other, each of said trays further including adjacent its downstream end, and overflow pipe positioned transversely at approximately the center of said tray, said overflow pipe extending upwardly in such relation to the vertical dimensions of said tray that overflow of water occurs only when said tray is nearly filled with water; and

means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby.

10. A dehumidifier as defined in claim 9 further including,

a vertical duct extending into a forward end of said housing, said duct having, an upper end positioned outside said housing supplied with the heated, moisture laden air; and an open, discharge end positioned near the bottom of said housing adjacent a forward end thereof,-

said trays having their forward ends positioned adjacent and spaced from said duct extending rearwardly therefrom.

11. A dehumidifier as defined in claim 9 wherein said overflow pipe of at least one of said trays has its lower end immersed below the .water level in the next of said traysunderneath said one tray.

12. A laundry dryer ofthe type including a generally rectangular cabinet in which is mounted a perforated drum rotating about a horizontal axis and in which heated air is passed through the drum to dry the laundry, access to the interior of the drum being through an opening defined by an annular wall extending concentrically into the drum through the cabinet, the annular wall being provided at one point with a peripherally extending outlet slot for the passage of air leaving the drum, the laundry dryer including,

a generally rectangular housing mounted within the cabinet below the drum,

a plurality of generally horizontal, water filled shallow trays mounted within said housing in overlapped vertically spaced relation, said trays being arranged to cause a downward zigzag flow of water from one said try to the next,

a duct communicating with said opening in said an nular wall, said duct extending downwardly through said housing to a position adjacent the bottom thereof, air discharged from said drum passing across the trays within said housing thereby cooling and dehumidifying the air; and

a lint filter connected with said duct overlying said opening, said lint filter having a narrow slit shaped opening therein extending across the entire width of said filter.

13. A dehumididfier as defined in claim 12 wherein said slit is positioned peripherally in the last third of said lint filter in the direction of rotation of the drum.

14. A laundry dryer as defined in claim 12 further includding.

rigid flanges connected with said annular wall extending along and stiffening the edges of said slit in said lint filter.

15. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising, i

a generally rectangular housing mounted within the cabinet,

a plurality of generlly horizontal, water filled, shallow trays mounted within said housing in overlapped, vertically spaced relation, said trays being arranged to cause a downward zigzag flow of water from one said tray to the next;

means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby;

a vertical duct extending into a forward end of said UNITED STATES PATENT OFFICE" I CERTIFICATE OF CORRECTION PATENT N0. 3,866,333

DATED February 18, 1975 INVENTOR(S) Georg Sarukhanian et a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Change inventor's name from "Georg Sarukahanian" to --Georg Sarukhanian- Column 1, line 7, change "air produce" to --air produced- 1 Column 3, line 42, change "deownstream" to ---downstream-- Column 4, line 65, change "In additional" to --In addition-- Column 5, line 17, change "to cooled" to --too cooled-- Column 5, line 22, change "provent" to :;g gfprevent Column 6, line 40 (claim 2) change "inclined protion" to -inclined portion-- Column 8, line 10 (claim 9) change "try" to --tray- Column 8, line 54 (claim 12) change "try" to -tray- Column 9, line 2 (claim 14) change "includding" to -including--- Column9, line 14 (claim 15) change "generlly" to--generally Signed and sealed this 29th day of April 1975. i

(SEAL) I I k g Attest: v C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Atteeting Officer and Trademark;

FORM PO-lOSO (IO-69] USCOMM-DC 6037G-P69 u. s. covilmlnn' murmur, ornce 930 

1. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising, a generally rectangular housing mounted within the cabinet, a plurality of generally horizontal, water filled, shallow trays mounted within said housing in overlapped, vertically spaced relation, said trays extending in a generally longitudinal direction with the flow of water along each said tray being from one longitudinal end to the other, each said tray further including adjacent its downstream end an overflow pipe positioned transversely at approximately the center of said tray, said overflow pipe extending upwardly in such relation to the vertical dimensions of said tray that overflow of water occurs only when said tray is nearly filled with water, each being configured so as to have longitudinally extending, downwardly curved portions positioned on either transverse side of said overflow pipe with a drain opening positioned at the lowest point of curvature, said trays being arranged to cause a downward zigzag flow of water from one said tray to the next, and means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby.
 2. A dehumidifier for removing water from heated, moistuRe laden air produced during the drying of laundry the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising, a plurality of generally horizontal, water filled, shallow trays, a generally rectangular housing mounted within the cabinet, said trays being mounted within said housing in overlapped, vertically spaced relation and being arranged so as to cause a downward zigzag flow of water from one tray to the next, said housing extending in a rearward direction from the forward wall of the cabinet, and including a first downwardly and rearwardly inclined protion spaced above and adjacent a leading end of the uppermost of said trays, said first portion of said housing directing the flow of air downwardly against said tray, a second inclined portion of said housing extending from a position adjacent the rear edge of said first portion inclined upwardly and extending rearwardly, and a third portion of said housing extending vertically between the adjacent ends of said first and second inclined portions of said housing, and means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby.
 3. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising, a plurality of generally horizontal, water filled shallow trays, a generally rectangular housing mounted within the cabinet, said trays being mounted within said housing in overlapped, vertically spaced relation and being arranged so as to cause a downward zigzag flow of water from one tray to the next, said housing extending in a rearward direction from the forward wall of the cabinet and including a first downwardly and rearwardly inclined portion spaced above and adjacent a leading end of the uppermost of said trays, said first portion of said housing directing the flow of air downwardly against said tray, a second inclined portion of said housing extending from a position adjacent the rear edge of said first portion inclined upwardly and extending rearwardly, and a dependent, transversely extending lip secured to said second inclined portion of said housing adjacent the rear end thereof, and means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby.
 4. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising, a generally rectangular housing mounted within the cabinet, a plurality of generally horizontal, water filled, shallow trays mounted within said housing in overlapped, vertically spaced relation, said trays being arranged to cause a downward zigzag flow of water from one said tray to the next; means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby; a vertical duct extending into a forward end of said housing, said duct having an upper end positioned outside said housing supplied with the heated, moisture laden air, and an open, discharge end positioned near the bottom of said housing adjacent a forward end thereof, said trays having their forward ends positioned adjacent and spaced from said duct extending rearwardly therefrom, said duct decreasing progressively in cross-sectional area toward said discharge end thereby increasing the velocity of the air flow entering said housing.
 5. A dehumidifier as defined in claim 4 wherein said housing is positioned adjacent the front wall of the cabinet of the machine, and includes a forward wall defined by an adjacent portion of the forward wall of the cabinet, said housing further comprising a service door mounted in said housing forward wall for providing access to the interior of said housing and means for removably mounting said trays therewithin.
 6. A dehumidifier as defined in claim 4 wherein each of said trays is formed of sheet material provided with raised beads along its peripheral edges, said trays being arranged at a slight inclination to the horizontal and being provided with raised projections extending substantially transversely to the flow direction of the water within said tray.
 7. A dehumidifier as defined in claim 4 further including, a sump in the bottom of said housing for collecting water, said sump positioned vertically beneath said discharge end of said duct.
 8. A dehumidifier as defined in claim 4 wherein said housing further includes, guiding surfaces connected with said housing extending downwardly and toward the upper surface of the uppermost of said trays for guiding the flow of air against the water in said uppermost of said trays.
 9. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising, a generally rectangular housing mounted within the cabinet, a plurality of generally horizontal, water filled, shallow trays mounted within said housing in overlapped, vertically spaced relation, said trays being arranged to cause a downward zigzag flow of water from one said try to the next, said trays extending in a generally longitudinal direction with the flow of water along each said tray being from one longitudinal end to the other, each of said trays further including adjacent its downstream end, and overflow pipe positioned transversely at approximately the center of said tray, said overflow pipe extending upwardly in such relation to the vertical dimensions of said tray that overflow of water occurs only when said tray is nearly filled with water; and means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby.
 10. A dehumidifier as defined in claim 9 further including, a vertical duct extending into a forward end of said housing, said duct having, an upper end positioned outside said housing supplied with the heated, moisture laden air; and an open, discharge end positioned near the bottom of said housing adjacent a forward end thereof, said trays having their forward ends positioned adjacent and spaced from said duct extending rearwardly therefrom.
 11. A dehumidifier as defined in claim 9 wherein said overflow pipe of at least one of said trays has its lower end immersed below the water level in the next of said trays underneath said one tray.
 12. A laundry dryer of the type including a generally rectangular cabinet in which is mounted a perforated drum rotating about a horizontal axis and in which heated air is passed through the drum to dry the laundry, access to the interior of the drum being through an opening defined by an annular wall extending concentrically into the drum through the cabinet, the annular wall being provided at one point with a peripherally extending outlet slot for the passage of air leaving the drum, the laundry dryer including, a generally rectangular housing mounted within the cabinet below the drum, a plurality of generally horizontal, water filled shallow trays mounted within said housing in overlapped vertically spaced relation, said trays being arranged to cause a downward zigzag flow of water from one said try to the next, a duct communicating with said opening in said annular wall, said duct extending downwardly through said housing to a position adjacent the bottom thereof, air discharged from said drum passing across the trays within said housing thereby cooling and dehumidifying the Air; and a lint filter connected with said duct overlying said opening, said lint filter having a narrow slit shaped opening therein extending across the entire width of said filter.
 13. A dehumididfier as defined in claim 12 wherein said slit is positioned peripherally in the last third of said lint filter in the direction of rotation of the drum.
 14. A laundry dryer as defined in claim 12 further includding, rigid flanges connected with said annular wall extending along and stiffening the edges of said slit in said lint filter.
 15. A dehumidifier for removing water from heated, moisture laden air produced during the drying of laundry, the dehumidifier being mounted in a laundry machine of the type having a generally rectangular cabinet provided with a generally vertical forward wall, the dehumidifier comprising, a generally rectangular housing mounted within the cabinet, a plurality of generlly horizontal, water filled, shallow trays mounted within said housing in overlapped, vertically spaced relation, said trays being arranged to cause a downward zigzag flow of water from one said tray to the next; means for guiding the air across said trays to cause the air to be cooled and dehumidified thereby; a vertical duct extending into a forward end of said housing, said duct having an upper end positioned outside said housing supplied with the heated, moisture laden air, and an open, discharge end positioned near the bottom of said housing adjacent a forward end thereof, said trays having their forward ends positioned adjacent and spaced from said duct extending rearwardly therefrom, said duct further including a vertically extending rear wall adjacent said trays, and a second wall disposed in closely spaced generally coextensive, parallel relation to said rear wall, said walls defining an insulating space therebetween. 